Automotive air conditioning and other refrigerating systems commonly employ an accumulator between the outlet of the evaporator and the inlet of the compressor to receive a mixture of gaseous and liquid refrigerant fluid and liquid oil from the evaporator and deliver gaseous refrigerant fluid, with a small amount of atomized oil therein, to the compressor. The accumulator traps the remainder of the liquid oil and liquid refrigerant fluid to prevent slugs of liquid being drawn into the compressor, which would cause damage thereto.
A common form of accumulator, as shown in U.S. Pat. No. 3,488,678 has a U shaped tube therein with one leg of the U having an inlet opening at the upper part of the accumulator, the bottom of the U at the lower part of the accumulator, and the other leg of the U extending through the wall of the accumulator near the upper end thereof. The bottom portion of the U has a bleed port therein to permit oil in the bottom portion of the accumulator to enter the U shaped tube and to become dispersed in atomized form in the refrigerant gas passing through the U shaped tube to the exterior of the accumulator.
In such accumulators, the U tube must be of relatively large full capacity, such as 3/4 inch O.D. or larger. Such tubes cannot be bent to a very small radius to form the U and the accumulator container must be of a rather large diameter so as to accomodate the U bend. As for example, a U tube of 3/4 inch O.D. must have a radius of about 11/2 inches to prevent wrinkling or flattening and therefore the container must be about 5 inches outside diameter or larger, in order to contain the U tube. This makes the container bulkier than it otherwise need be.
U.S. Pat. No. 3,837,177 discloses an accumulator in which telescoped straight tubes replace a U tube but the construction does not lend itself to use of inlet and outlet parts through the side wall of the container, as is required in many installations, nor are the telescoped tubes supported radially at both ends for better support thereof.